<template>
  <div>
    <div class="goods">
      <div class="menu-wrapper" ref="menuWrapper">
        <ul>
          <li v-for="(item,index) in goods" class="menu-item" :class="{'current':currentIndex===index}" @click="selectMenu(index,$event)">
            <span class="text border-1px">
            <span v-show="item.type>0" class="icon" :class="classMap[item.type]"></span>{{item.name}}
            </span>
          </li>
        </ul>
      </div>
      <div class="foods-wrapper" ref="foodsWrapper">
        <ul>
          <li v-for="item in goods" class="food-list food-list-hook">
            <h1 class="title">{{item.name}}</h1>
            <ul>
              <li @click="selectFood(food,$event)" v-for="food in item.foods" class="food-item border-1px">
                <div class="icon">
                  <img width="57" height="57" :src="food.icon" alt="">
                </div>
                <div class="content">
                  <h2 class="name">{{food.name}}</h2>
                  <p class="desc">{{food.description}}</p>
                  <div class="extra">
                    <span>月售{{food.sellCount}}份</span>
                    <span>好评率{{food.rating}}%</span>
                  </div>
                  <div class="price">
                    <span class="now">￥{{food.price}}</span><span v-show="food.oldPrice" class="old">￥{{food.oldPrice}}</span>
                  </div>
                  <div class="cartcontrol-wrapper">
                    <cartcontrol :food="food" @cartAdd="handleCartAdd"></cartcontrol>
                  </div>
                </div>
              </li>
            </ul>
          </li>
        </ul>
      </div>
      <shopcart ref="shopcart" :select-foods="selectFoods" :delivery-price="seller.deliveryPrice" :min-price="seller.minPrice"></shopcart>
    </div>
    <Food :food="selectedFood" ref="food"  @cartAddOfFood="handleCartAdd"></Food>
  </div>
</template>

<script type="text/ecmascript-6">
  import BScroll from 'better-scroll'
  import axios from 'axios'
  import shopcart from 'components/shopcart/shopcart'
  import cartcontrol from 'components/cartcontrol/cartcontrol'
  import Food from 'components/food/food'
  const ERR_OK = 0

  export default {
    props: {
      seller: {
        type: Object
      }
    },
    data() {
      return {
        goods: [],
        listHeight: [],
        scrollY: 0,
        selectedFood: {}
      }
    },
    computed: {
      currentIndex() {
        for (let i = 0; i < this.listHeight.length; i++) {
          let height1 = this.listHeight[i]
          let height2 = this.listHeight[i + 1]
          if (!height2 || (this.scrollY >= height1 && this.scrollY < height2)) {
            return i
          }
        }
        return 0
      },
      selectFoods() {
        let foods = []
        this.goods.forEach((good) => {
          good.foods.forEach((food) => {
            if (food.count) {
              foods.push(food)
            }
          })
        })
        return foods
      }
    },
    created() {
      this.classMap = ['decrease', 'discount', 'special', 'invoice', 'guarantee']
      axios.get('/api/goods').then((response) => {
        const res = response.data
        if (res.errno === ERR_OK) {
          this.goods = res.data
          this.$nextTick(() => {
            this._initScroll()
            this._calculateHeight()
          })
        }
      })
    },
    methods: {
      selectMenu(index, event) {
        if (!event._constructed) {
          return
        }
        let foodList = this.$refs.foodsWrapper.getElementsByClassName('food-list-hook')
        let el = foodList[index]
        this.foodsScroll.scrollToElement(el, 100)
      },
      selectFood(food, event) {
        if (!event._constructed) {
          return
        }
        this.selectedFood = food
        this.$refs.food.show()
      },
      // 体验优化，异步执行下落动画
      _drop(target) {
        this.$nextTick(() => {
          this.$refs.shopcart.drop(target)
        })
      },
      _initScroll() {
        this.meunScroll = new BScroll(this.$refs.menuWrapper, {
          click: true
        })
        this.foodsScroll = new BScroll(this.$refs.foodsWrapper, {
          click: true,
          probeType: 3
        })
        this.foodsScroll.on('scroll', (pos) => {
          this.scrollY = Math.abs(Math.round(pos.y))
        })
      },
      _calculateHeight() {
        let foodList = this.$refs.foodsWrapper.getElementsByClassName('food-list-hook')
        let height = 0
        this.listHeight.push(height)
        for (let i = 0; i < foodList.length; i += 1) {
          let item = foodList[i]
          height += item.clientHeight
          this.listHeight.push(height)
        }
      },
      handleCartAdd(target) {
        this._drop(target)
      }
    },
    components: {
      shopcart,
      cartcontrol,
      Food
    }
  }

</script>

<style lang="scss" rel="stylesheet/scss">
  @import "../../common/scss/mixin.scss";
  .goods {
    display: flex;
    position: absolute;
    top: 174px;
    bottom: 46px;
    width: 100%;
    overflow: hidden;
    .menu-wrapper{
      flex: 0 0 80px;
      width: 80px;
      background: #f3f5f7;
      .menu-item{
        display: table;
        height: 54px;
        width: 56px;
        line-height: 14px;
        padding: 0 12px;
        &.current{
          position: relative;
          z-index: 10;
          margin-top: -1px;
          background: #fff;
          font-weight: 700;
          border-left: 2px solid #3091e8;
          @include border-none();
        }
        .icon {
          display: inline-block;
          vertical-align: top;
          width: 12px;
          height: 12px;
          margin-right: 2px;
          background-size: 12px 12px;
          background-repeat: no-repeat;
          &.decrease {
            @include bg-image('decrease_3');
          }
          &.discount {
            @include bg-image('discount_3');
          }
          &.guarantee {
            @include bg-image('guarantee_3');
          }
          &.invoice {
            @include bg-image('invoice_3');
          }
          &.special {
            @include bg-image('special_3');
          }
        }
        .text{
          display: table-cell;
          font-size: 12px;
          vertical-align: middle;
          @include border-1px(rgba(7,17,27,0.1));
        }
      }
    }
    .foods-wrapper{
      flex:1;
      .title{
        padding-left: 14px;
        height: 26px;
        line-height: 26px;
        border-left: 2px solid #d9dde1;
        font-size: 12px;
        color: rgb(147,153,159);
        background: #f3f5f7;
      }
      .food-item{
        display: flex;
        margin:18px;
        padding-bottom: 18px;
        @include border-1px(rgba(7,17,27,0.1));
        &:last-child{
          @include border-none();
          margin-bottom: 0;
        }
        .icon{
          flex: 0 0 57px;
          margin-right: 10px;
        }
        .content{
          flex: 1;
          .name{
            margin: 2px 0 8px 0;
            height: 14px;
            line-height: 14px;
            color: rgb(7,17,27);
          }
          .desc,.extra{  
            line-height: 10px;
            font-size: 10px;
            color: rgb(147,153,159);
          }
          .desc {
            margin-bottom: 8px;
          }
          .extra{
            &.count{
              margin-right: 12px;
            }
          }
          .price{
            font-weight: 700;
            line-height: 24px;
            .now{
              margin-right: 8px;
              font-size: 14px;
              color: rgb(240,20,20);
            }
            .old{
              text-decoration: line-through;
              font-size: 10px;
              color: rgb(147,153,159);
            }
          }
          .cartcontrol-wrapper{
            position: absolute;
            right: 0;
            bottom: 12px;
          }
        }
      }
    }


  }
</style>
